Recent RF devices, such as contactless transponder cards (e.g. Smartcards, e-Passports, Tickets, etc.) and NFC (Near Field Communication) devices, are capable of performing half-duplex bi-directional communication with a reader device. Thus, these RF devices are capable of operating in a receiving mode as well as in a transmitting mode. In the transmitting mode, RF devices may utilize active load modulation to transmit the information or data. In order to optimize the transmission, the antenna circuit of the RF device is tuned to the carrier frequency of the reader device, e.g. to 13.56 MHz in systems complying with ISO/IEC 14443 and NFC standards. However, such an antenna configuration is usually not ideal for use in the receiving mode, as the shape of the reader modulation may experience a negative impact. Similarly, an antenna configuration optimized for the receiving mode is usually not ideal for use in the transmitting mode.
There may thus be a need for a way of improving the conditions for bi-direction communication between RF devices.